I still prefer the blockier look of the '13 - '14 models. I used to own an 08 convertible and '13 coupe. That V6 is plenty of grunt for having some fun, and tame enough to be a daily driver.
The only reason I sold it is because the kids are bigger now and they don't fit in the back. I still want to take a '15 out for a spin just to feel how different it is, but if I was in the market, I'd probably go for a '13 GT. Part of the appeal is the rough ride and butch looks. I came away unimpressed from the autoshow too. Other than that awesome arse on the '15, it's still kinda of 'meh' overall for me. Yes the interior is better, but the refresh from '10 model year was still the best pony car interior out there.
My '13 was a little floaty, you could really feel the weight of the front end so I'd be interested to feel how much better it is now.